DOC AIRBUS | AMM A320FOIL BREATHER SYSTEM - DESCRIPTION AND OPERATION
** ON A/C NOT FOR ALL
1. Component Location
** ON A/C NOT FOR ALL | FIN | FUNCTIONAL DESIGNATION | PANEL | ZONE | ACCESS DOOR | ATA REF |
|---|---|---|---|---|---|
| ** ON A/C NOT FOR ALL | |||||
| 6006EM | DEOILER | 400 | 79-23-41 | ||
Oil Distribution SystemA. The engine oil breather system removes air from the bearing compartments, isolates the breather air from the oil and release the air overboard.
(1) Deoiler
(a) The deoiler is located on the rear of the Main Gearbox (MGB) at approximately the 8 o'clock position.
1 The breather air from the oil tank deaerator, the No. 3 bearing compartment and the No. 5 and No. 6 bearing compartment flows to the deoiler which isolates the scavenge oil from the air.
2 The oil drains into the MGB and mixes with the gearbox scavenge oil.
3 Breather air from the deoiler goes through the deoiler air exit duct to be sent overboard.
4 The air/oil scavenge mixture from the front bearing compartment (No. 1, 1.5, 2, and FDG), and No. 3, 4, 5 and 6 bearing compartments flows to the lubrication and scavenge oil pump.
5 The pump sends the mixture to the oil tank deaerator which isolates the breather air from the scavenged oil. The oil flows into the oil tank.
6 The breather air flows through the oil tank pressurization valve and goes to the MGB. The MGB breather then sends air/oil mixture to the deoiler.
(2) Deoiler Air Exit Duct
(a) The deoiler, which is on the MGB, sends isolated breather air overboard through the deoiler air exit duct.
(b) The air exit duct is attached to the rear of the deoiler housing with bolts.
(c) The deoiler air exit duct is a line replaceable unit.
(3) Auxiliary Oil System
(a) An auxiliary lubrication system is included to make sure that the journal bearings will get oil while a flight or windmill condition occurs.
(b) System components:
1 Fan oil pump
2 Journal Oil Shuttle Valve (JOSV)
3 Auxiliary oil reservoir
4 FDG gutter
5 Gravity valve.
(c) Operation
1 This system has a single function fan oil pump located in the front bearing compartment. It is operated by the fan rotor that supplies pressure to the JOSV which usually will bypass the oil back to the oil tank. If the JOSV senses a low pressure (when a windmill operation or a zero or negative G event occurs), it will send this oil to the journal bearings to make sure there is sufficient lubrication of the journal bearings.
2 The pump will get oil from the compartment sump or an isolated auxiliary reservoir through the gravity valve.
3 The gravity valve has a small weight which is sensitive to pressure differentials and the gravity vector.
4 For zero or negative G conditions, the pump will get oil through the gravity valve from the isolated auxiliary reservoir. This reservoir is located internally in the No. 1 and 1.5 bearing compartment adjacent to the gear assembly.
5 To make sure the reservoir is always full, the total oil flow for the gear system is thrown off the ring gear flange into a 360 degree FDG gutter. The high tangential velocity forces the oil into the reservoir. All the oil from the gear is not necessary to make sure the journal bearings are sufficiently lubricated, so the unwanted oil is bypassed to the compartment sump.
6 For ground windmill operations, the pump will get oil through the gravity valve from the compartment sump, which is continuously filled by the recycled oil that moves from the gear system and main shaft bearings. The small quantity of oil supplied in ground windmill operation will prevent journal bearing damage.